American  Society  of  Municipal 
Improvements,  1915 

SPECIFICATIONS  FOR 

Bituminous  Concrete  with  One  Pro 
duct  of  Stone  Crushing  Plant 

ADOPTED  OCTOBER  14,  1915 


These  specifications  will  be  modified  from  time  to  time 
to  keep  them  fully  up  to  date.     Suggestions  as  to 
modifications    or    additions   are    solicited   and 
should  be  sent  to  the  Secretary,  or  to  A.  H. 
Blanchard,  Columbia  University,  New- 
port City,  Chairman  of  the  Sub- 
Committee  on   Specifications 
for    Broken    Stone    and 
Gravel  Roads,  and — 


GEORGE     W.     TILLSON 

Boro  Hall,  Brooklyn,  New  York 
Chairman  of  General  Committee  on  Standard  Specifications 


COPYRIGHTED,  1916  -;.;    ' 

Any  municipality  which  is  represented  in  the  membership  of  the  Society  by  one  or  more 
city  officials,  will  be  given  free  permission  to  use  these  specifications  or  any 
part  of  them  upon  application  to  the  Secretary 


PUBLISHED  BY  THE  SOCIETY 
CHARLES  CARROLL  BROWN,  Secretary 

702  WULSIN  BUILDING 
INDIANAPOLIS,  INDIANA 


SPECIFICATIONS    FOR    A    BITUMINOUS    CONCRETE 

PAVEMENT  MINERAL  AGGREGATE  COMPOSED 

OF  ONE  PRODUCT  OF  A  STONE  CRUSHING 

PLANT. 

General  Description.  The  bituminous  concrete  wearing  course 
shall  consist  of  a  compact  mixture  of  broken  stone  and  asphalt 
cement  or  refined  tar  laid  to  conform  to  the  required  grades  and 
cross  sections,  covered  with  a  seal  coat  of  asphalt  cement  and 
broken  stone  chips,  and  constructed  as  hereinafter  specified. 

Broken  Stone. 

Quality.  All  broken  stone  shall  be  clean,  rough  surfaced  and 
sharp  angled,  of  compact  texture  and  uniform  grain. 

Tests.  The  broken  stone  shall  be  subjected  to  abrasion  and 
toughness  tests  conducted  by  the  engineer  in  accordance  with  methods 
adopted  by  the  American  Society  for  Testing  Materials,  August 
15,  1908.  The  broken  stone  used  for  the  construction  of  the 
wearing  course  shall  show  a  loss  on  abrasion  of  not  more  than  3.5 
per  cent  or  a  French  coefficient  of  wear  of  not  less  than  11.5,  and 
its  toughness  shall  not  be  less  than  13.0. 

Broken  Stone  Chips.  Broken  stone  chips  shall  consist  of  the 
product  of  a  stone  crushing  plant  obtained  by  passing  the  broken 
stone  through  a  section  of  a  rotary  screen  having  circular  openings 
three-eighths  (%)  or  one-half  (l/>}  inch  in  diameter  and  over  a 
screen  having  openings  of  one-eighth  (%)  or  one-quarter  (%) 
inch. 

Broken  Stone  for  Mineral  Aggregate.  Broken  stone  for  the 
mineral  aggregate  of  the  wearing  course  shall  consist  of  one  product 
of  a  stone  crushing  and  screening  plant.  It  shall  conform  to  the 
following  mechanical  analysis,  using  laboratory  screens  having  cir- 
cular openings:  All  of  the  broken  stone  shall  pa^s  a  one  and  one- 
quarter  (1^4)  inch  screen;  not  more  than  ten  (10)  per  cent  nor 
less  than  one  (1)  per  cent  shall  be  retained  upon  a  one  (1)  inch 
screen;  not  more  than  ten  (10)  per  cent  nor  less  than  three  (3)  per 
cent  shall  pass  a  one-quarter  ( Vj )  mch  screen. 


342939 


Heating.  Before  entering  the  mixer,  the  broken  stone  for  the 
mineral  aggregate  shall  be  heated  until  thoroly  dry  to  between 
66°  C.  (150°  F.)  and  121°  C.  (250°  F.),  as  directed,  in  revolv- 
ing driers  in  which  no  flame  shall  be  permitted  to  come  in  contact 
with  the  broken  stone  and  in  which  the  broken  stone  shall  be  con- 
tinuously agitated  during  the  heating. 

Bituminous  Cement. 

Asphalt  Cement  and  Refined  Tar.  The  asphalt  cement  or  refined 
tar  used  in  the  construction  of  the  wearing  course  of  the  bituminous 
concrete  pavement  shall  conform  with  either  one  of  the  specifica- 
tions covering  the  chemical  and  physical  properties  of  bituminous 
cement  included  under  the  item  entitled  "Asphalt  Cements  and  Re- 
fined Tars  for  Wearing  Course  of  Bituminous  Concrete  Pavement." 
If  asphalt  cement  is  used  in  the  bituminous  concrete  wearing  course, 
the  same  asphalt  cement  shall  be  used  for  the  seal  cost.  If  refined 
tar  is  used  in  the  bituminous  concrete  wearing  course,  an  asphalt 
cement  shall  be  used  in  the  seal  coat  and  shall  conform  with  either 
one  of  the  specifications  covering  the  physical  and  chemical  proper- 
ties of  asphalt  cements  included  under  the  item  entitled  "Asphalt 
Cements  for  Seal  Coat  for  Bituminous  Concrete  Pavement." 

Previous  Service.  The  contractor  will  be  required  to  show,  to 
the  satisfaction  of  the  engineer,  that  the  company  manufacturing  the 
asphalt  cement  or  refined  tar  he  proposes  to  use  under  a  given  speci- 
fication has,  for  a  period  of  at  least  two  years,  manufactured  asphalt 
cement  or  refined  tar  in  a  thoroly  equipped  plant,  and  that  asphalt 
cement  or  refined  tar  manufactured  of  bituminous  material  obtained 
from  a  similar  source  to  that  which  he  proposes  to  use,  shall  have 
been  in  continuous  and  successful  use  for  a  period  of  at  least  two 
years  in  bituminous  pavements  constructed  by  the  mixing  method 
previous  to  the  date  of  the  letting  in  which  his  proposal  was  sub- 
mitted. 

Heating.  The  asphalt  cement  or  refined  tar  shall  be  heated  in 
kettles  so  designed  as  to  admit  of  even  heating  of  the  entire  mass, 
with  an  efficient  and  positive  control  of  the  heat  at  all  times. 
Asphalt  cement  shall  be  heated  as  directed  to  a  temperature  between 
135°  C.  (275°  F.)  and  177°  C.  (350°  F.).  All  asphalt  cement 
heated  beyond  177°  C.  (350°  F.),  either  before  or  during  mixing 
with  the  broken  stone,  shall  be  rejected.  Refined  tar  shall  be  heated 

2 


as  directed  to  a  temperature  between  93°  C.  (200°  F.)  and  135° 
C.  (275°  F.).  All  tar  heated  beyond  135°  C.  (275°  F.),  either 
before  or  during  mixing  with  broken  stone,  shall  be  rejected.  No 
tar  shall  be  heated  in  kettles  containing  any  asphalt  cement  and  in 
like  manner  no  asphalt  cement  shall  be  heated  in  kettles  containing 
any  tar.  Before  changing  from  one  type  of  material  to  the  other, 
kettles  shall  be  scrupulously  cleaned  in  order  to  avoid  mixtures  of 
the  two.  Any  such  mixtures  resulting  from  this  cause  shall  be 
rejected. 

Thermometers  Furnished  by  Contractor.  The  contractor  shall 
provide  a  sufficient  number  of  accurate,  efficient,  stationary  ther- 
mometers for  determining  the  temperatures  of  the  asphalt  cement  or 
refined  tar  in  kettles. 


Construction  of  Wearing  Course 

Mixing.  When  thoroly  heated  to  the  temperature  directed,  the 
asphalt  cement  or  refined  tar  and  the  broken  stone  for  the  bituminous 
concrete  shall  be  mixed  so  that  the  resulting  mixture  shall  contain 
between  five  (5)  and  eight  (8)  per  cent  by  weight  of  bitumen,  as 
directed,  depending  primarily  upon  the  kind  of  bituminous  cement 
and  mineral  aggregate  which  are  used.  A  mixer  shall  be  used, 
having  revolving  blades,  and  so  designed  and  operated  as  to  produce 
and  discharge  a  thoroly  coated  and  uniform  mixture  of  non-segre- 
gated broken  stone  and  bituminous  cement.  When  discharged,  mix- 
tures of  asphalt  cement  and  broken  stone  shall  have  a  temperature 
not  more  than  149°  C.  (300°  F.)  and  not  less  than  93°  C.  (200° 
F.)  as  directed.  When  discharged,  mixtures  of  refined  tar  and 
broken  stone  shall  have  a  temperature  not  more  than  121°  C.  (250° 
F.)  and  not  less  than  66°  C.  (150°  F.). 

Surface  of  Foundation.  Before  laying  the  bituminous  concrete, 
the  surface  of  the  cement-concrete  foundation  shall  be  dry  and  thor- 
oly cleaned.  If  any  defective  areas  exist  in  the  cement-concrete 
foundation,  they  shall  be  repaired  as  directed  at  least  ten  (10)  days 
in  advance  of  laying  the  bituminous  concrete.  In  cases  where  ce- 
ment-concrete edging  is  not  used,  compacted  shoulders,  forming  a 
continuation  of  the  surface  of  the  foundation,  shall  be  constructed. 
A  two  (2)  inch  plank  shall  be  laid  on  each  shoulder  at  the  edge  of 
the  foundation.  These  planks  shall  remain  in  place  until  after  the 
seal  coat  has  been  finished. 


Prevention  of  Dust.  The  shoulders  of  the  road  and  adjacenf 
grounds  shall  be  sufficient  sprinkled  during  the  placing  of  bitumin 
ous  material  wherever  there  would  otherwise  be  danger  of  clouds  ol 
dust  blowing  over  the  pavement. 

Laying  Bituminous  Concrete.  The  bituminous  concrete,  heated 
and  prepared  as  specified,  shall  be  delivered  direct  from  the  mixer 
to  the  point  of  deposition  on  the  foundation  in  trucks  or  wagons, 
provided  with  canvas  covers  for  retaining  the  heat.  As  delivered 
the  bituminous  concrete  shall  have  a  temperature  of  at  least  66° C. 
(150°  F.).  Material  having  a  lower  temperature  than  this  shall 
not  be  laid  upon  the  foundation.  The  hot  bituminous  concrete 
shall  be  dumped  upon  platforms,  constructed  as  directed,  and 
shoveled  with  hot  shovels  into  position  on  the  foundation.  The 
bituminous  concrete  shall  be  immediately  uniformly  spread  over  the 
foundation  course  by  men  experienced  in  such  work  and  thoroly 
compacted  by  rolling.  When  compacted  the  wearing  course  shall 
have  a  thickness  at  no  place  of  less  than  two  (2)  inches  and  shall  be 
free  from  surface  depressions  and  irregularities.  The  paving  shall  be 
done  as  continuously  as  practicable,  to  reduce  to  a  minimum  the 
number  of  joints  between  hot  and  cold  materials.  Such  joints  shall 
be  constructed  as  directed. 

Rolling.  The  bituminous  concrete  wearing  course,  laid  as  speci- 
fied above,  shall  be  rolled  at  once,  while  the  mixture  is  warm  and 
pliable,  beginning  at  the  edges  and  working  toward  the  center. 
Means  for  preventing  the  bituminous  material  from  adhering  to  the 
roller  without  injury  to  the  bituminous  concrete,  shall  be  provided. 
Rolling  shall  continue  without  interruption  until  all  roller  marks 
disappear  and  the  surface  shows  no  further  compressibility.  Places 
which  the  roller  cannot  effectively  reach  shall  be  compacted  with 
hot  iron  tampers. 

Roller.  Rollers  used  on  the  bituminous  concrete  shall  be  wrell 
balanced,  self-propelled,  tandem  rollers,  weighing  between  ten  (10) 
and  twelve  (12)  tons  each.  Each  shall  have  a  compression  under 
the  rear  roller  of  between  two  hundred  and  fifty  (250)  and  three 
hundred  and  fifty  (350)  pounds  per  linear  inch  of  roll,  and  shall 
be  provided  with  an  ash  pan,  which  shall  prevent  ashes  from  drop- 
ping onto  the  bituminous  concrete  or  seal  coat. 

Testing  Surface.  Before  placing  the  seal  coat,  the  surface  of  the 
bituminous  concrete  shall  be  tested  wtih  a  four  (4)  foot  straight 


edge  laid  longitudinally  upon  any  portion  of  the  surface,  and  any 
depression  or  other  irregularity  exceeding  three-eighths  (^)  inch 
shall  be  satisfactorily  eliminated. 

Seal  Coat.  As  soon  as  possible  after  the  compaction  of  the 
bituminous  concrete,  when  the  surface  is  clean  and  dry,  a  seal  coat 
of  the  hot  asphalt  cement  shall  be  evenly  distributed  over  the 
bituminous  concrete  and  uniformly  spread  by  means  of  squeegees. 
The  asphalt  cement  shall  be  applied  at  a  temperature  not  less  than 
135°  C.  (275°F.),  nor  more  than  177°  C.  (350°  F.),  at  a  rate  of 
one-half  (l/2)  to  one  (1)  gallon  per  square  yard,  as  directed.  A 
thin,  uniform  layer  of  dry,  clean  broken  stone  chips  shall  be  imme- 
diately uniformly  spread  in  two  applications  over  the  asphalt  cement 
by  machines  or  skilled  workmen.  Each  application  of  broken  stone 
chips  shall  be  rolled  twice  by  a  self-propelled,  tandem  roller.  The 
spreading  of  the  broken  stone  chips  shall  not  lag  more  than  twenty 
(20)  feet  behind  the  placing  of  the  asphalt  cement  coating.  Broken 
stone  chips  shall  not  be  placed  on  the  wearing  course  before  the 
asphalt  cement  of  the  seal  coat  is  applied.  The  surface  of  the  bitu- 
minous concrete  shall  be  kept  scrupulously  clean  until  the  seal  coat 
is  applied,  and  the  contractor  shall  not  permit  any  hauling  over  the 
wearing  course  before  the  completion  of  the  seal  coat. 

Seasonal  and  Weather  Limitations.  No  bituminous  concrete  shall 
be  mixed  or  placed  when  the  air  temperature  in  the  shade  is  below 
10°  C.  (50°  F.). 

Payment. 

Measurement  and  Payment.  The  quantity  of  bituminous  con- 
crete wearing  course  to  be  paid  for  under  this  item  shall  be  the  num- 
ber of  square  yards,  measured  horizontally,  satisfactorily  completed 
in  accordance  with  the  specifications.  The  price  stipulated  in  this 
item  shall  include  the  furnishing,  crushing  and  screening  of  the 
broken  stone,  including  the  broken  stone  chips  for  the  seal  coat,  and 
heating,  mixing,  placing  and  rolling  of  the  broken  stone  and  the 
asphalt  cement  or  refined  tar,  and  all  work  and  expenses  incidental 
to  the  completion  of  the  bituminous  concrete  and  the  seal  coat, 
except  the  furnishing  of  the  bituminous  cement,  which  will  be  in- 
cluded for  payment  under  the  item  "Asphalt  Cements  and  Refined 
Tars  for  Wearing  Course  of  Bituminous  Concrete  Pavement"  or  the 
items  " Asphalt  Cements  and  Refined  Tars  for  Wearing  Course  of 
Bituminous  Concrete  Pavement"  and  "Asphalt  Cements  for  Seal 


Coat  for  Bituminous  Concrete  Pavement."  Measurement  under  this 
item  shall  not  include  any  pavement  repaired  or  relaid,  except  as 
provided  for  in  the  following  paragraph. 

Removing  and  Replacing  Wearing  Course.  If  the  contractor 
removes,  as  directed,  portions  of  the  wearing  course,  and  the  work 
thus  exposed  for  examination  is  found  satisfactory,  or  if  for  any 
reason  he  shall  be  ordered  to  remove  wearing  course  built  in  full 
accordance  with  his  contract,  he  shall  be  paid  for  such  excavation 
one-fourth  the  price  per  square  yard  stipulated  in  this  item.  If  the 
wearing  course  after  examination  is  found  to  be  of  acceptable  quality, 
the  original  wearing  course  will  be  paid  for  as  well  as  that  used  to 
refill  the  excavation.  In  connection  with  the  removing  and  replacing 
of  the  wearing  course  in  accordance  wTith  this  paragraph,  no  quantity 
shall  be  measured  as  less  than  one  square  yard. 


SPECIFICATIONS  FOR  ASPHALT  CEMENTS  AND  REFINED  TARS  FOR 
WEARING  COURSE  OF  BITUMINOUS  CONCRETE  PAVEMENT 
AND  FOR  ASPHALT  CEMENTS  FOR  THE  SEAL  COAT  IF  AN 
ASPHALT  CEMENT  is  USED  IN  THE  BITUMINOUS  WEARING 
COURSE. 


Asphalt  Cement   "A"   Optional  With  Asphalt   Cements   "B,"   "C," 
"D,"  "E"  and  Refined  Tars  "F"  and  "G." 


(  1  )      The  asphalt  cement  shall  be  homogeneous,  free  from  watei 
and  shall  not  foam  when  heated  to   177°   C.    (350°  F.). 

(2)      It  shall  show  a  flash  point  of  not  less  than  205°  C.   (40O 


(3)  Its  specific  gravity   at   a  temperature  of  25°   C.    (77°   F.) 
shall  be  not  less  than  0.970  nor  more  than   1.000. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same   results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°  F.),  from  75  to  90;  200  gram  load,  1  minute,  at  4°  C.   (39° 
F.),  not  less  than  35;  50  gram  load,  5  seconds,  at  46°  C.  (115°  F.), 
not  more  than  250. 

6 


(5)  Its  melting  point  as  determined  by  the  cube  method  shall 
be  not  less  than  55°  C.   (131°  F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of    163°   C.    (325°   F.)    for  5   hours  in  an  open  cylin- 
drical tin  dish,  5*/2  centimeters  (about  21/^  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3^   centimeters    (about    \l/2 
inches)    in  depth,  the  loss  in  weight  shall  not  exceed   1.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°  Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°  and  55°   C.    (104°   and 
131°  F.)  to  the  extent  of  not  less  than  70.0  per  cent  nor  more  than 
80.0  per  cent  of  its  bitumen  as  determined  by  clause   (7). 

(10)  It  shall   yield   not  less  than   8.0  per  cent   nor  more   than 
12.0  per  cent  of  fixed  carbon. 


Asphalt   Cement   "B"   Optional   with   Asphalt   Cements   "A,"    "C," 
UD,"  "E"  and  Refined  Tars  "F"  and  "G." 


( 1 )  The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to   177°  C.    (350°  F.). 

(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.). 

(3)  Its  specific  gravity   at  a  temperature  of  25°   C.    (77°   F.) 
shall  be  not  less  than  1.000  nor  more  than  1.030. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same  results 


as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°  F.),  from  90  to  100;  200  gram  load,  1  minute  at  4°  C.  (39: 
F.),  not  less  than  30. 

(5)  Its  melting  point  as  determined   by  the  cube  method  shall 
be  not  less  than  50°  C.   (122°  F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of   163°   C.    (325°   F.)    for  5   hours  in  an  open  cylin- 
drical tin  dish,  ^l/2  centimeters  (about  2l/\.  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3*/2   centimeters    (about   \l/2 
inches)    in  depth,  the  loss  in  weight  shall  not  exceed   1.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7).  . 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°   and  55°   C.    (104°   and 
131°  F.)  to  the  extent  of  not  less  than  72.0  per  cent  nor  more  than 
78.0  per  cent  of  its  bitumen  as  determined  by  clause  (7). 

(10)  It  shall  yield  not  less  than   11.0  per  cent  nor  more  than 
15.0  per  cent  of  fixed  carbon. 


Asphalt  Cement  "C"  Optional  With  Asphalt  Cements  "A,"   "B," 
"D,"  "E"  and  Refined  Tars  "F"  and  "G." 

( 1 )  The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to   177°  C.   (350°  F.). 

(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.). 

8 


(3)  Its  specific  gravity  at  a  temperature  of  25°   C.    (77°    F.) 
shall  be  not  less  than   1.030  nor  more  than   1.040. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer   giving  the  same   results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°  F.),  from  70  to  90;  200  gram  load,  1  minute,  at  4°  C.  (39° 
F.),  not  less  than  10. 

(5)  Its  melting  point  as  determined  by  the  cube  method  shall 
be  not  less  than  45°  C.    (113°  F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of   163°   C.    (325°   F.)    for  5   hours  in  an  open  cylin- 
drical tin  dish,  5T/2  centimeters  (about  2*4  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3^2   centimeters    (about   \l/2 
inches)    in  depth,   the  loss  in  weight  shall  not  exceed  2.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°  and  55°   C.    (104°   and 
131°  F.)  to  the  extent  of  not  less  than  80.0  per  cent  nor  more  than 
88.0  per  cent  of  its  bitumen  as  determined  by  clause   (7). 

(10)  It  shall  yield  not  less  than   10.0  per  cent  nor  more  than 
14.0  per  cent  of  fixed  carbon. 


Asphalt  Cement  "D"  Optional  With  Asphalt  Cements  "A,"   "B," 
"C,"  "E"  and  Refined  Tars  "F"  and  "G." 

( 1 )      The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to  177°  C.   (350°  F.). 

9 


(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.). 

(3)  Its  specific  gravity  at   a  temperature  of  25°   C.    (77°   F.) 
shall  be  not  less  than   1.025  nor  more  than  1.050. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer   giving  the  same   results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°  F.),  from  85  to  95;  200  gram  load,  1  minute,  at  4°  C.   (39° 
F.),  not  less  than  20. 

(5)  Its  melting  point  as  determined   by  the  cube  method  shall 
be  not  less  than  50°   C.(    122°   F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of   163°   C.    (325°   F.)    for  5   hours  in  an  open  cylin- 
drical tin  dish,  5T/2  centimeters  (about  21/^  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3^   centimeters    (about   \y2 
inches)    in  depth,  the  loss  in  weight  shall  not  exceed  2.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
.5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°   and  55°   C.    (104°   and 
131°   F.),   to  the  extent  of  not  less  than  67.0  per  cent  nor  more 
than  77.0  per  cent  of  its  bitumen  as  determined  by  clause    (7). 

(10)  It  shall  yield  not  less  than    12.0  per  cent  nor  more  than 
18.0  per  cent  of  fixed  carbon. 

10 


Asphalt  Cement   "E"   Optional  With  Asphalt  Cements   "A,"   "B," 
"C,"  "D"  and  Refined  Tars  "F"  and  "G." 

( 1 )  The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to   177°'  C.   (350°  F.). 

(2)  It  shall  show  a  flash  point  of  not  less  than  165°  C.   (329° 
F-). 

(3)  Its  specific  gravity   at   a  temperature  of  25°   C.    (77°    F.) 
shall  be  not  less  than  1.040  nor  more  than  1.060. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same  results 
as  the  Dow  machine),  it  shall  show  penetrations  w7ithin  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°   F.),  from   140  to   160;  200  gram  load,   1   minute,  at  4°   C. 
(39°  F.),  not  less  than  40. 

(5)  When  tested  by  means  of  the  New  York  Testing  Labora- 
tory Float  Apparatus,  the  float  shall  not  sink  in  water  maintained 
at  66°   C.    (150°   F.)    in  less  than   120  seconds  nor  more  that   180 
seconds. 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of    163°   C.    (325°    F.)    for  5  hours  in  an  open  cylin- 
drical  tin    dish,    5l/2    centimeters    (about   21/^    inches)    in    diameter, 
with  vertical  sides  measuring  approximately  3^   centimeters    (about 
\l/2   inches)    in  depth,   the  loss  in  weight  shall  not  exceed   3.0  per 
cent  of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  be  not  less  than  93.0 
per  cent  nor  more  than  98.0  per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than   98.5   per  cent 
of  its  bitumen  as  determined  by  clause   (7). 

11 


(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°   and  55°   C.    (104°   and 
131°  F.)  to  the  extent  of  not  less  than  75.0  per  cent  nor  more  than 
85.0  per  cent  of  its  bitumen  as  determined  by  clause    (7). 

(10)  It  shall  yield  not  less  than   11.0  per  cent  nor  more  than 
15.0  per  cent  of  fixed  carbon. 

(11)  Upon    ignition   it   shall   yield   not   less   than    1.0   per   cent 
nor  more  than  3.0  per  cent  of  ash. 


Refined  Tar  "F"  Optional  With  Asphalt  Cements  "A,"  "B,"  "C," 
"D,"  "E"  and  Refined  Tar  "G." 

( 1 )  The  refined  tar  shall  be  homogeneous,  free  from  water  and 
shall  not  foam  when  heated  to   150°   C.    (302°   F.). 

(2)  Its  specific  gravity  at   a  temperature  of  25°    C.    (77°    F.) 
shall  be  not  less  than  1.160  nor  more  than  1.200. 

(3)  When  tested  by  means  of  the  New  York  Testing  Labora- 
tory Float  Apparatus,  the  float  shall  not  sink  in  water  maintained 
at  50°   C.    (122°   F.)    in  less  than   140  seconds  nor  more  than   170 
seconds. 

(4)  Its   bitumen   as   determined    by   its   solubility   in   chemically 
pure  carbon  disulphide  at  room  temperature  shall  be  not  less  than 
95.0  per  cent  and  it  shall  show  not  more  than  0.2  per  cent  ash  upon 
ignition  of  the  material  insoluble  in  carbon  disulphide. 

(5)  When    distilled    according   to    the   tentative   method    recom- 
mended  by   Committee    D-4   of   the   American    Society   for   Testing 
Materials  in  1911,  it  shall  yield  no  distillate  at  a  temperature  lower 
than    170°   C.    (338°   F.)  ;   not  more   than   7.0  per  cent  by  weight 
shall  distill  below  270°  C.  (518°  F.),  and   not  more  than   20.0   per 
cent  by  weight  shall  distill  below  300°  C.  (572°  F.). 

(6)  The  total  distillate  from  the  test  made  in  accordance  with 
clause   (5)   shall  have  a  specific  gravity  at  a  temperature  of  25°  C. 
(77°  F.)   of  not  less  than  1.000  nor  more  than  1.020. 

(7)  The   melting   point,    as   determined    in    water   by   the   cube 
method,  of  the  pitch  residue  remaining  after  distillation  to  300°  C. 
(572°    F.),   in   accordance   with   the   test   described    in   clause    (5), 
shall  be  not  more  than  75°  C.   (167°  F.). 

12 


Refined  Tar  "G"  Optional  With  Asphalt  Cements  "A,"  "B,"  "C," 
"D,"   "E"  and   Refined  Tar   "F." 

( 1 )  The  refined  tar  shall  be  homogeneous,  free  from  water  and 
shall  not  foam  when  heated  to   150°   C.    (302°   F.). 

(2)  Its  specific  gravity  at   a  temperature  of  25°    C.    (77°   F.) 
shall  be  not  less  than  1.200  nor  more  than  1.300. 

(3)  When  tested  by  means  of  the  New  York  Testing  Labora- 
tory Float  Apparatus,  the  float  shall  not  sink  in  water  maintained 
at  50°  C.    (122°   F.)    in  less  than   140  seconds  nor  more  than   170 
seconds. 

(4)  Its   bitumen   as   determined   by   its   solubility   in   chemically 
pure  carbon  disulphide  at  room  temperature  shall  be  not  less  than 
75.0  per  cent  nor  more  than  90.0  per  cent,  and  it  shall  not  show 
more  than  0.2  per  cent  ash  upon  ignition  of  the  material  soluble  in 
carbon  disulphide. 

(5)  When    distilled    according   to    the   tentative   method    recom- 
mended  by   Committee    D-4   of   the   American    Society   for   Testing 
Materials  in  1911,  it  shall  yield  no  distillate  at  a  temperature  lower 
than   170°   C.    (338°   F.)  ;  not  more  than   10.0  per  cent  by  weight 
shall  distill  below  270°  C.  (518°  F.),  and   not  more  than   20.0  per 
cent  by  weight  shall  distill  below  300°  C.  (572°  F.). 

(6)  The  total  distillate  from  the  test  made  in  accordance  with 
clause   (5)   shall  have  a  specific  gravity  at  a  temperature  of  25°  C. 
(77°  F.)  of  not  less  than  1.030. 

(7)  The   melting   point,    as    determined    in   water   by    the   cube 
method,  of  the  pitch  residue  remaining  after  distillation  to  300°  C. 
(572°    F.),    in   accordance   with    the   test   described   in   clause    (5), 
shall  be  not  more  than  75°   C.   (167°  F.). 


SPECIFICATIONS  FOR  ASPHALT  CEMENTS  FOR  SEAL  COAT  FOR 
BITUMINOUS  CONCRETE  PAVEMENT  WHEN  REFINED  TAR  is 
USED  IN  THE  BITUMINOUS  CONCRETE  WEARING  COURSE. 

Asphalt  Cement  "H"  Optional  With  Asphalt  Cements  "K"  and  "L." 

(1)      The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam' when  heated  to   177°  C.    (350°  F.). 

13 


(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.)- 

(3)  Its  specific  gravity   at   a  temperature  of  25°   C.    (77°   F.) 
shall  be  not  less  than  0.970  nor  more  than  1.000. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same  results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°    F.),    from   60   to    75;   200   gram   load,    1    minute,    at   4°    C. 
(39°    F.),   not  less  than  50;  50   gram  load,   5   seconds,   at  46°    C. 
(115°  F.),  not  more  than  150. 

(5)  Its  melting  point  as  determined   by  the  cube  method  shall 
be  not  less  than  80°   C.    (176°   F.). 

.(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of  163°  C.  (325°  F.)  for  5  hours  in  an  open  cylin- 
drical tin  dish,  5j/2  centimeters  (about  2^4  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3j/2  centimeters  (about  ll/2 
inches)  in  depth,  the  loss  in  weight  shall  not  exceed  1.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

.  (7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
:arbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°   and  55°   C.    (104°   and 
131°  F.)  to  the  extent  of  not  less  than  70.0  per  cent  nor  more  than 
80.0  per  cent  of  its  bitumen  as  determined  by  clause    (7). 

(10)  It  shall   yield   not   less  than   8.0   per  cent  nor  more  than 
12.0  per  cent  of  fixed  carbon. 

14 


Asphalt  Cement  "K"  Optional  With  Asphalt  Cements  "H"  and  "L." 

( 1 )  The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to   177°  C.   (350°  F.). 

(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.). 

(3)  Its  specific  gravity   at  a  temperature  of  25°   C.    (77°   F.) 
shall  be  not  less  than  1.030  nor  more  than  1.045. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same  results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°    F.),   from   60   to   70;   200   gram  load,    1    minute,   at   4°    C. 
(39°   F.),  not  less  than   18;  50  gram  load,   5  seconds,   at  46°    C. 
(115°  F.),  not  more  than  270. 

(5)  Its  melting  point  as  determined  by  the  cube  method  shall 
be  not  less  than  60°   C.   (140°   F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of   163°   C.    (325°   F.)    for  5   hours  in  an  open  cylin- 
drical tin  dish,  5^  centimeters  (about  2}/\  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3^   centimeters    (about   \l/> 
inches)    in  depth,   the  loss  in  wreight  shall  not  exceed    1.0  per  cent 
of  the  original  wreight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon   disulphide  at   room  temperature  shall   not  be  less  than  99.5 
per  cent. 

(8)  It  shall  be  soluble  in  chemically  pure  carbon  tetrachloride 
at  room  temperature  to  the  extent  of  not  less  th?n  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°  and  55°   C.    (104°   and 

15 


131°  F.)  to  the  extent  of  not  less  than  70.0  per  cent  nor  more  than 
80.0  per  cent  of  the  bitumen  as  determined  by  clause   (7). 

(10)      It  shall  yield  not  less  than    12.0  per  cent  nor  more  than 
16.0  per  cent  of  fixed  carbon. 


Asphalt  Cement  "L"  Optional  with  Asphalt  Cements  "H"  and  "K." 

( 1 )  The  asphalt  cement  shall  be  homogeneous,  free  from  water 
and  shall  not  foam  when  heated  to   177°  C.    (350°   F.). 

(2)  It  shall  show  a  flash  point  of  not  less  than  205°  C.   (400° 
F.). 

(3)  Its  specific  gravity   at   a  temperature  of  25°    C.    (77°    F.) 
shall  be  not  less  than  1.025  nor  more  than  1.055. 

(4)  When  tested  with  a  standard  No.  2  needle  by  means  of  a 
Dow  penetrometer    (or  other  penetrometer  giving  the  same   results 
as  the  Dow  machine),  it  shall  show  penetrations  within  the  follow- 
ing limits  for  the  conditions  stated,  the  penetrations  being  expressed 
in  hundredths  of  a  centimeter:  100  gram  load,  5  seconds,  at  25°  C. 
(77°  F.),  from  60  to  70;  200  gram  load,  1  minute,  at  4°  C.   (39° 
F.),  not  less  than  16. 

(5)  Its  melting  point  as  determined   by  the  cube  method  shall 
be  not  less  than  55°  C.   (131°  F.). 

(6)  When  50  grams  of  the  material  is  maintained  at  a  uniform 
temperature  of   163°   C.    (325°   F.)    for  5  hours  in  an  open  cylin- 
drical tin  dish,  5y^  centimeters  (about  2}/\  inches)  in  diameter,  with 
vertical  sides  measuring  approximately  3^   centimeters    (about   \]/2 
inches)    in  depth,   the  loss  in  weight  shall   not  exceed    1.0  per  cent 
of  the  original  weight  of  the  sample. 

The  penetration  of  the  residue,  when  tested  as  described  in  clause 
(4)  with  a  standard  No.  2  needle  under  a  load  of  100  grams,  for 
5  seconds  at  25°  C.  (77°  F.)  shall  be  not  less  than  one-half  the 
penetration  of  the  original  material  tested  under  the  same  conditions. 

(7)  Its  bitumen  as  determined  by  its  solubility  in  chemically  pure 
carbon  disulphide  at  room  temperature  shall  not  be  less  than  99.5 
per  cent. 

16 


(8)  It  shall   be  soluble  in  chemically  pure  carbon   tetrachloride 
at  room  temperature  to  the  extent  of  not  less  than  99.5  per  cent  of 
its  bitumen  as  determined  by  clause   (7). 

(9)  It  shall  be  soluble  in  86°  to  88°   Baume  paraffin  naphtha, 
at  least  85  per  cent  distilling  between  40°  and  55°   C.    (104°   and 
131°  F.),  to  the  extent  of  not  less  than  67.0  per  cent  nor  more  than 
77.0  per  cent  of   its  bitumen  as  determined   by  clause    (7). 

(10)  It  shall  yield  not  less  than    13.0  per  cent  nor  more  than 
18.0  per  cent  of  fixed  carbon. 

Delivery.  The  asphalt  cement  or  refined  tar  shall  be  delivered 
in  suitable  containers,  far  enough  in  advance  of  its  use  in  the  work 
to  permit  the  necessary  tests  to  be  made.  Each  container  shall  be 
plainly  labeled  with  the  trade  name  of  the  asphalt  cement  or  refined 
tar,  name  of  manufacturer,  gross  weight  and  net  weight.  Each 
shipment  and  each  carload  shall  be  kept  separate. 

Bills  of  Lading.  The  contractor  shall  furnish  the  engineer  on  or 
before  the  arrival  of  each  shipment  at  or  near  the  site  of  the  work, 
bills  of  lading,  or  correct  copies  thereof,  which  shall  state  the  trade 
name  of  the  asphalt  cement  or  refined  tar,  and  the  name  and 
address  of  the  company  manufacturing  and  supplying  it. 

Samples.  Samples  will  be  taken  by  the  engineer  from  each  carload 
of  asphalt  cement  or  refined  tar  when  delivered  at  the  work,  unless 
satisfactory  arrangements  can  be  made  for  sampling  before  shipment. 
Such  samples  shall  be  analyzed  by  the  engineer  to  assure  the  delivery 
of  an  asphalt  cement  or  refined  tar  of  the  specified  quality  and  to 
determine,  for  purpose  of  payment,  the  quantity  of  bitumen. 

Work  Included.  Under  this  item  the  contractor  shall  furnish 
and  deliver  on  the  work  at  such  points  as  directed  an  asphalt  cement 
or  an  asphalt  cement  and  a  refined  tar,  which  conform  with  the 
specifications  heretofore  mentioned.  All  asphalt  cement  or  refined 
tar  for  any  pavement  of  a  given  contract  shall  be  furnished  by  one 
manufacturer  and  no  change  in  type  or  grade  of  bituminous  cement 
used  in  the  bituminous  concrete  or  the  seal  coat  shall  be  allowed  in 
any  pavement  of  a  given  contract  without  written  permission  from 
the  engineer. 

Measurement  and  Payment.  The  quantity  of  bitumen  in  the 
asphalt  cement  or  refined  tar,  to  be  paid  for  under  this  item, 

17 


shall  be  the  number  of  tons,  determined  in  accordance  with  the  para- 
graph headed  "Samples,"  contained  in  the  asphalt  cement  or  refined 
tar  placed  in  the  pavement  in  accordance  with  the  specifications  and 
requirements,  or  used  as  directed  for  other  purposes.  The  percentage 
of  bitumen  determined  by  an  average  of  the  analyses  of  the  acceptable 
samples  taken  by  the  engineer  during  a  given  month,  shall  be  used 
as  the  basis  for  payment  for  the  asphalt  cement  or  refined  tar  used 
during  that  month.  Asphalt  cement  or  refined  tar  that  is  wasted 
shall  not  be  included  in  the  measurement  under  this  item.  The 
price  stipulated  in  this  item  shall  include  the  cost  of  furnishing, 
hauling  and  delivering  the  asphalt  cement  or  refined  tar  at  points 
on  the  work  where  it  is  to  be  used,  and  all  expenses  incidental 
thereto. 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


